The chemistry of polynuclear compounds. Part 31. Synthesis of undecacarbonylhydridotriosmate(1–) and its reaction with octadeca-carbonylhexaosmium to give a carboxylate-bridged anionic enneaosmium species

Abstract

Treatment of [Os3(CO)12] with KOH in MeOH gives the anion [Os3H(CO)11]–; low-temperature 13C n.m.r. spectroscopy reveals that the structure of this hydrido-cluster is the same as that established for [Fe3H(CO)11]– in the solid state; at higher temperatures, fluxional behaviour similar to that previously observed for [Fe3H(CO)11]– occurs. The [Os3H(CO)11]– anion reacts with [Os6(CO)18] to produce the Os9, anion [(OC)10HOS3(µ-CO2)Os6(CO)17]– which contains an Os3, and Os6 unit linked by a CO2, group. Carbon- 13 n.m.r. spectroscopic studies reveal that the C atom of the CO2 linkage arises from the [OS6(CO)18].